On Wednesday night, United Launch Alliance’s first Vulcan Centaur rocket successfully tested its Blue Origin-built BE-4 main engines, removing one of the two remaining technical obstacles before the launcher is given the green light for its first voyage later this year.
At 9:05 p.m. EDT on Wednesday (0105 UTC Thursday), the Vulcan rocket’s two BE-4 engines ignited and fired for almost six seconds, producing over a million pounds of thrust while hold-down straps maintained the launcher securely in place at pad 41.
ULA’s Vulcan rocket programme vice president Mark Peller called the launch a “huge milestone.” This is as close as you can get to launching a rocket without actually launching it. This is an integrated test of all the airborne elements and the ground systems working together, simulating the conditions of launch day right down to starting the main engine.
Peller referred to the Flight Readiness Firing as “our last major milestone on the path to launch” of the first Vulcan Centaur rocket.
On Wednesday afternoon, the ULA launch team loaded methane, liquid hydrogen, and liquid oxygen propellants into the Vulcan first stage and its Centaur upper stage, and then the countdown clock was paused for several hours so that engineers could assess whether or not a lightning strike near the launch pad had affected any critical systems.
At T-minus 7 minutes, the launch team was polled to ensure everything was ready to go, and the countdown resumed from a built-in hold. The Vulcan Centaur rocket then switched to internal power, and the propellant tanks were pressurised to flight levels.
At T minus 5 seconds, the crew started up the twin engines. The BE-4s were brought up to around 60% power for two seconds before being turned off by the rocket’s flight computer. Pad 41’s flame trench, which faces east, was the source of the exhaust plume produced by the test fire.
ULA CEO Tory Bruno exclaimed, “Nominal run!” in a tweet.
Jeff Bezos’ Blue Origin company constructed both of the BE-4 engines used in the Vulcan rocket. Blue Origin’s New Glenn rocket, which is currently in the prototype stage, will employ a cluster of seven BE-4 engines.
There is “nothing sweeter in rocketry than the word nominal,” Bezos tweeted late Wednesday. “You and the team deserve a lot of credit, Tory.”
The two BE-4 engines of the Vulcan rocket are seen in this still from the Flight Readiness Firing on Wednesday night. To be ready for Tuesday’s test fire at Cape Canaveral Space Force Station, United Launch Alliance ULA personnel moved the Vulcan Centaur rocket from its vertical hangar to pad 41.
Before the first Vulcan test flight could take place, a number of tests and countdown rehearsals had to take place at Cape Canaveral. On May 12, the launch crew at ULA tanked the Vulcan rocket and its Centaur upper stage with methane, liquid hydrogen, and liquid oxygen.
In order to make “adjustments” to the Vulcan Centaur rocket after the tanking test on May 12, ULA brought it back to the Vertical Integration Facility. According to Tory Bruno, ULA’s CEO, modifications were made to the topping rate for liquid oxygen, the flow of purge and chill gas to the BE-4 engine igniters, and a setting with ground hydraulic pressure.
After making the necessary adjustments, ground crews were scheduled to conduct the Flight Readiness fire on May 25. However, ULA postponed the test fire because of an issue with the BE-4 engine’s ignition system. ULA moved the Vulcan launcher back to pad 41 on Tuesday after returning it from the hangar for troubleshooting.
ULA claims that during the Flight Readiness Firing, it mounted new instruments on the rocket to track how well the engines were functioning. Over the following several weeks, engineers will examine test-firing data to ensure everything performed as planned.
However, the first Vulcan Centaur flight’s scheduled launch date is still unknown.
According to ULA, final ground testing of the Vulcan rocket’s Centaur upper stage constitutes the remaining work on the certification programme. In March, a hydrogen explosion at NASA’s Marshall Space Flight Centre in Huntsville, Alabama, interrupted a structural test of the Vulcan’s Centaur upper stage.
Both the test stand and a Centaur upper stage test item were damaged in the explosion. ULA’s Atlas 5 rocket, which is presently in service, employs a version of the Centaur upper stage that has been expanded and improved for use on the Vulcan rocket.
The first Vulcan test flight might take place as soon as this summer if engineers assess that the Centaur top stage of the rocket requires no adjustments. Bruno said last month that the mission might be postponed until later this year if maintenance is needed on the Centaur.
Launch plans will be developed “pending the data review and the investigation results,” ULA said in a statement released Wednesday night. Launching only when we are certain it is safe to do so, testing is a crucial aspect of our launch vehicle development programme.
On January 25th, within the Vertical Integration Facility at Cape Canaveral Space Force Station, ULA placed the first stage for the first Vulcan rocket test flight onto a mobile launch platform. ULA is responsible for this launch.
In 2006, Lockheed Martin and Boeing integrated its Atlas and Delta rocket programmes into a single entity called United Launch Alliance (ULA). Depending on the specifics of the mission, the Vulcan rocket may be launched in a variety of configurations, with a range of strap-on solid rocket boosters and payload fairing sizes.
The first stage of the Vulcan rocket, which measures 17.7 feet (5.4 metres) in diameter, is painted in brilliant colours in preparation for the program’s first test flight. Neither the solid rocket boosters nor the payload fairing are attached to the Vulcan rocket during the tanking tests or the Flight Readiness Firing. The total height of the vehicle in such setting is about 50.7 metres (166 ft).
ULA intended to empty the rocket’s fuel tanks and bring the Vulcan Centaur back to the hangar once the test shooting was finished so that it could be inspected. The heat blankets protecting the engines during testing may have become singed, requiring technicians to readjust or replace them. ULA will also replace the BE-4 engine’s disposable igniters before proceeding with final launch preparations.
Blue Origin’s new BE-4 engines, which run on methane, will make their debut on the Vulcan rocket’s first voyage. Each BE-4 engine has the potential to produce around 550,000 pounds of thrust when running at maximum power. There will be two of them powering each Vulcan core stage, with zero, two, four, or six solid rocket boosters providing initial impulse.
Two solid-fuel boosters produced by Northrop Grumman and a payload shroud manufactured by Beyond Gravity (previously Ruag Space) will be installed by ground crews.
The Centaur 5 upper stage of the Vulcan rocket is superior to the Centaur 4 and Centaur 3 stages presently used by ULA on the Atlas 5 rocket. The Centaur 5 is bigger in diameter so that its two Aerojet Rocketdyne RL10 engines and cryogenic hydrogen and oxygen propellant tanks can fit. When riding the Atlas 5 rocket, the Centaur normally only uses one of its engines.
Launch of the first Vulcan Centaur rocket from United Launch Alliance from Cape Canaveral Space Force Station occurred last month. ULA is responsible for this launch.
When all Vulcan rocket variants are operational, the new rocket will completely replace and expand upon the lift capabilities supplied by all of ULA’s rockets at now. In comparison to ULA’s Delta 4-Heavy, which utilises three interconnected liquid-fueled first stage boosters, the biggest Vulcan rocket type, which will begin flying in the next several years, will have more payload lift capabilities due to its single core stage and enhanced upper stage engines.
With its improved upper stage engines, the Vulcan Centaur can send as much as 27.2 tonnes of cargo into low Earth orbit.
The BE-4 engines used in Vulcan launches will be recovered for reuse by ULA in the future, but not the whole first stage.
As of 2015, ULA had planned to launch the Vulcan rocket for the first time in 2019. In 2018, the BE-4 engine from Blue Origin was chosen to power the company’s first stage rocket. ULA planned to conduct the first Vulcan test flight in 2020.
The first Vulcan test flight was pushed back by a few years because to difficulties with the development and testing of the BE-4 engine. Before the first Vulcan launch, Blue Origin and ULA completed final certification testing of the BE-4 engine, according to Bruno earlier this month, removing a potential roadblock.
The first mission for the Vulcan rocket will include the launch of an Astrobotic commercial moon lander that will aim to deliver a number of NASA experiments and technology demonstration payloads to the lunar surface. The Commercial Lunar Payload Services Programme allows NASA to send payloads to the moon using privately owned spacecraft, such as the Peregrine lander built by Astrobotic.
The first Vulcan launch will also include two test satellites for Amazon’s Kuiper broadband network.
For the next five years, the United States Space Force will use ULA’s Vulcan rocket to deploy the vast majority of its huge national security satellites. Two “certification flights” are needed for the Vulcan rocket before it can be used for national security launch missions, according to the Pentagon.
Sierra Space’s Dream Chaser spaceplane, a new resupply ship for the International Space Station, is scheduled for a second Vulcan test flight in early 2024. Then the first Vulcan launch with a national security military payload will occur.
